Refrigerant distributors for refrigerant circuits have already been known in general for many years from the prior art and are used, in particular, in air conditioning systems of motor vehicles.
Thus, for example, U.S. Pat. No. 3,745,787 discloses a refrigerant distributor of the generic type which is arranged between an expansion valve and an evaporator of a vehicle air conditioning system. A refrigerant of the air conditioning system is usually present in the region of the refrigerant distributor as a liquid/gas mixture and is customarily to be distributed by way of the refrigerant distributor to individual sections of the evaporator in a manner which is as uniform as possible both in relation to the liquid phase and in relation to the gas phase. In order to achieve this, a baffle face is provided at the inlet opening of the inlet channel, which baffle face is to ensure turbulence in the liquid/gas mixture and is correspondingly to ensure distribution of the refrigerant to the outlet channels of the refrigerant distributor in a manner which is as uniform as possible.
Particularly uniform refrigerant distribution to the individual sections of the air conditioning system evaporator advantageously ensures a high cooling capacity of the evaporator. However, certain distribution inhomogeneities, for example as a result of thermal conduction within the evaporator or a suitable addition of fresh air, can be compensated for without relatively great problems or technical disadvantages.
In contrast, the cooling of high-performance accumulators or batteries in hybrid or electric vehicles presents disproportionately greater technical challenges for the refrigerant circuit in the motor vehicle.
In contrast to the climate control of the interior compartment of the vehicle, cooling of the drive battery is necessary even at low ambient temperatures (down to approximately −10° C.). At low ambient temperatures of this type, in some circumstances the refrigerant in the region of the refrigerant distributor is completely in its liquid phase, and the refrigerant circuit has only very low pressure differences of the order of magnitude of approximately 1 bar between the high pressure region and the low pressure region.
Otherwise, the performance and service life of the accumulators or batteries is greatly dependent on the temperature, with the result that particularly reliable and homogeneous cooling to a temperature which is as constant as possible is very important.
Furthermore, the drive battery of a hybrid or electric vehicle is frequently divided into a plurality of separate drive battery modules which are assigned in each case one evaporator. As a consequence, the individual evaporators are structurally separated from one another, with the result that thermal equalization via thermal conduction cannot take place.
Accordingly, in refrigerant circuits of hybrid or electric vehicles, uniform distribution is not necessarily desirable and technically advantageous, but rather individually adaptable distribution of the refrigerant to sections of the refrigerant circuit which are connected in parallel.